Inflight entertainment systems have evolved significantly over the last 25 years. Prior to 1978, IFE systems consisted of audio-only systems. In 1978, Bell and Howell (Avicom Division) introduced a group viewing video system based on video cassette tapes. In 1988, Airvision introduced the first in-seat video system allowing passengers to choose between several channels of broadcast video. In 1997, Swissair installed the first interactive video on demand (VOD) system. Currently, several inflight entertainment systems provide VOD with full digital video disc-like controls.
One factor in the commercial viability of an inflight entertainment system is the system's line replaceable units (LRUs). The term “LRU” is a term of art generally describing a complex component (e.g. “black box”) on an airplane that is designed to be replaced quickly on the flight line or airport ramp area. LRU's are beneficial because they are generally self-contained units that can be rapidly swapped-out in the event that maintenance is required thus allowing the airplane to continue to operate with little down time. To be installed on an airplane, an LRU design must first be approved by the Federal Aviation Administration by means defined in Title 14 of the Code of Federal Regulations. LRUs of a single hardware design configuration may have different software installed. An inflight entertainment system's installation costs, operating costs, maintenance costs and passenger comfort depend greatly on the size, form factor, number and weight of its LRUs, as well as the number of distinct LRUs deployed in a single aircraft and across an airline's entire fleet of aircraft.
FIG. 1 illustrates conventional inflight entertainment systems that employ a terrestrial-like VOD architecture (i.e. head end, distribution area, seat end). The left side of the figure shows components that are typically found at the head end of the system or in an electronics bay. The right side of the figure shows system components that are typically found at the seat end. The middle section of the figure shows system components that are typically found in a distribution area between the head end and the seat end. These components include area distribution boxes (ADBs) that fan-out data from the head end to the seat end. ADBs are typically connected to seat electronics boxes (SEBs) within each seat column, which distribute data forward and/or backward to an adjacent seat group in the same seat column.
Inflight entertainment system vendors have recently made attempts to reduce the number of distinct LRUs at the seat end. Four examples of conventional seat end architectures are shown in FIG. 1. Boxes A and D show traditional seat architectures wherein SEBs are interposed between ADBs and seat end components such as VDUs and passenger control units (PCUs). Boxes B and C show newer seat architectures that reflect attempts to eliminate or reduce reliance on SEBs by moving SEB functionality to VDUs and/or PCUs. This shift has generally come at the expense of increased VDU and/or PCU size, weight and power.
The inflight entertainment industry has been slower to reduce the number of distinct LRUs at the head end and in the distribution area. Moreover, conventional inflight entertainment systems require inter-area wiring and seat-to-seat wiring that varies across inflight entertainment system vendors and even across a single inflight entertainment system vendor's products, raising installation and maintenance costs.
Some small players in the inflight entertainment industry have made advances at the head end and in the distribution area. For example, one recent inflight entertainment system has no head end or distribution area. However, this system has no parallel in terrestrial VOD systems and cannot easily leverage advancements and technology developments from the terrestrial world. Another recent inflight entertainment system has a simplified head end that integrates the audio, video and application servers in a single LRU. However, this system is proprietary and cannot easily leverage advancements in terrestrial VOD system technology. Moreover, the latter system requires a network of distribution area nodes between the head end and the seat end.